Device for supplying therapeutic gas, particularly no or n2o, to a patient

ABSTRACT

Disclosed is a device for supplying therapeutic gas, notably NO/N2 or O2/N2O mixtures, including an internal passage with a valve for conveying and controlling the flow of therapeutic gas in the internal passage, a control unit controlling the valve, a graphic display for displaying choices that can be selected by a user, and a selector, such as touch-sensitive keys displayed on the graphic display for making a selection from among the selectable choices displayed on the graphic display. The control unit is configured to count a total number of patients treated by administration of the therapeutic gas from the selection, by a user, via the selector, of a first given choice corresponding to the start of a treatment by administering the therapeutic gas to a patient concerned.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to French Application No. 1912769 filedNov. 15, 2019, the entire contents of each of which are herebyincorporated by reference.

BACKGROUND OF THE INVENTION Field of the Invention

The present invention relates to a device for supplying therapeutic gas,particularly nitric oxide (NO) or nitrous oxide (N₂O), and also to aninstallation for administering gas to a patient comprising such atherapeutic-gas supply device.

Description of the Related Art

Inhaled nitric oxide, or NOi, is a gaseous medicament commonly used totreat patients suffering from acute pulmonary arterial hypertension,particularly pulmonary vasoconstrictions in adults or children,including the newborn (PPHN), as described for example in EP-A-560928 orEP-A-1516639.

An installation for applying NOi treatment, commonly referred to as anNO-administration installation, conventionally comprises one or morecylinders of NO/N₂ mixture supplying an NO-treatment administrationand/or monitoring device, a medical ventilator for delivering arespiratory gas, such as an O₂/N₂ mixture or air, to which the NO (i.e.NO/N₂) is added, and a patient kit notably comprising a respiratoryinterface, such as a tracheal tube, and one or more flexible pipes.

Such an NO-administration installation is used in a hospital environmentto administer the NOi treatment and thus care for hospitalized patientswho need to inhale NO in order to treat their pulmonary arterialhypertension.

Examples of such NO-administration installations are given in documentsWO-A-2012/094008, US-A-2015/320951, US-A-2015/273175, JP-A-H11192303,WO-A-02/40914 and US-A-2003/116159.

Now, the duration of patient treatment varies from one patient toanother, namely from a few hours up to several days. As a result, withinhospitals, it is very difficult to trace and record the number ofpatients who have been treated with NOi over a given period, for exampleof one or more months, or even an entire year, this being very differentfrom the case with the other medicaments, even though this informationregarding the number of patients treated is of utmost relevance to thehospitals which are obliged to guarantee correct use of the medicamentand to correlate the number of prescriptions against their hospitalactivity.

A similar range of problems also exists with other therapeutic gases,particularly equimolar mixtures of oxygen and nitrous oxide (MEOPA),i.e. O₂/N₂O mixtures, or even other medical gases.

In an attempt to address this problem, certain administration devices orgas cylinders count the number of hours of use of the therapeutic gas inorder from this, and on the basis of a fixed mean duration of use, todeduce an approximate number of patients treated.

Now, it will be appreciated that this approach is not ideal because itis based on a single mean duration, whereas the durations of use varygreatly from one patient to another. Thus it will be readily appreciatedthat the quantities of gas used in adults are very different from thoseused in newborns. The resulting calculation is therefore extremelyinaccurate, or even completely erroneous.

In addition, this approach also leads to errors because it relies oncalculations done by the user, who may make a mistake in performingthese calculations.

Finally, if a gas cylinder is inadvertently left open, the gas deliveredwill be considered as having been used to care for patients, even thoughit has been lost, and this once again will falsify the calculation.

The problem therefore is that of being able to accurately and reliablycount the number of patients treated by inhaling therapeutic gas,notably NO, which can be consulted at any moment by the user, such asthe care-giving staff, and which is automated in such a way as to supplyinformation that is useful to the user, and do so instantaneously,without the user having to perform the smallest of calculations forhimself, particularly in the context of the supply of NO/N₂ mixtures toa patient having need of such treatment, notably for treating theirpulmonary arterial hypertension or hypo-oxygenation of their blood.

SUMMARY OF THE INVENTION

A solution according to the invention therefore relates to a device forsupplying therapeutic gas, comprising:

-   -   an internal passage for conveying a flow of therapeutic gas        between (at least) a gas inlet and (at least) a gas outlet,    -   valve means for controlling the flow of therapeutic gas in the        internal passage,    -   control means configured to control at least the valve means,    -   a graphic display configured to display (at least) choices that        can be selected by a user, and possibly other information, and    -   selection means configured to make a selection from among the        selectable choices displayed on the graphic display.

According to the invention, the control means are configured to count atotal number (N) of patients treated by administration of thetherapeutic gas from the selection, by a user, via the selection means,of a first given choice corresponding to the start of a treatment byadministering the therapeutic gas to a patient concerned.

According to the embodiment considered, the therapeutic-gas supplydevice of the invention may comprise one or more of the followingfeatures:

-   -   the control means cooperate with the graphic display to display        the counted total number (N) of patients treated.    -   the control means comprise at least one microprocessor,        preferably at least one microcontroller.    -   said at least one microprocessor is arranged on an electronic        board.    -   the control means comprise at least one microprocessor using one        or more algorithms.    -   the selection means comprise one or more selection keys.    -   the graphic display comprises a display screen, typically a        digital screen, preferably a touchscreen.    -   the selection key or keys are one or more virtual keys displayed        on the touchscreen, namely one or more touch-sensitive keys.    -   the graphic display is configured to display the virtual        selection key(s) in the form of one or more selection windows.    -   the graphic display comprises a display screen in colour or in        black and white, or both.    -   the control means are configured to count a total number (N) of        patients treated by incrementing a patients counter,        particularly an internal counter of the microprocessor.    -   the control means are configured to increment the total        number (N) of patients treated by +1 in response to a selection,        by the user, of the first given choice corresponding to the        start of a treatment by administering therapeutic gas to a        patient concerned.    -   the control means are configured to operate the valve means and        begin a supply of therapeutic gas in response to a selection, by        the user, of the first given choice corresponding to the start        of a treatment by administering therapeutic gas to a patient        concerned.    -   alternatively, the control means are configured to operate the        valve means and begin a supply of therapeutic gas in response to        a selection, by the user, of the first given choice        corresponding to the start of a treatment by administering        therapeutic gas to a patient concerned, followed by a validation        (i.e. confirmation) of said selection of the first given choice,        said validation preferably being performed by the user selecting        a Validate key, particularly a virtual Validate key displayed on        the graphic display.    -   the control means are also configured to determine a total        duration of treatment for each patient treated which corresponds        to the period of time elapsed between the user selecting:        -   the first given choice corresponding to the start of a            treatment by administering the therapeutic gas to a patient            concerned, and        -   a second given choice corresponding to the end of the            treatment by administering the therapeutic gas to said            patient concerned.    -   the control means are further configured to:        -   temporarily interrupt the determining of the total duration            of treatment for a patient concerned after:            -   either the user selects the second choice corresponding                to the end of the treatment,            -   or the user selects a third given choice corresponding                to a suspension of treatment with temporary interruption                of the administration of therapeutic gas to said patient                concerned, and        -   resume determining the total duration of treatment for said            patient concerned after:            -   either the user reselects the first given choice                corresponding to the start of a treatment by                administering the therapeutic gas, that is to say makes                an additional selection of the first choice for the same                patient,            -   or the user selects a fourth given choice corresponding                to resumption of a treatment by administering the                therapeutic gas to said given patient.    -   the control means are also configured not to increment the        patients counter after the user reselects the first choice        corresponding to the start of a treatment or selects the fourth        choice corresponding to the resumption of treatment for a given        patient. This is because a reselection of the first choice or a        selection of the fourth choice is interpreted/considered by the        control means, particularly the microprocessor, to indicate the        resumption of the one same treatment of the one same patient,        following a temporary pause in this treatment in this patient.    -   the selection keys comprise:        -   a “Start treatment” key commanding the start of supply of            therapeutic gas, and        -   an “End treatment” key commanding the stopping of the supply            of therapeutic gas.    -   the “Start treatment” key and the “End treatment” key are the        one same key commanding the start and end of the supply of gas.    -   the “Start treatment” key and the “End treatment” key are        different keys.    -   the selection keys also potentially comprise:        -   a “Pause treatment” key commanding a pause in the supply of            therapeutic gas, and/or        -   a “Resume treatment” key commanding a resumption (following            a pause) of the supply of therapeutic gas.    -   the “Pause treatment” key and the “Resume treatment” key are the        one same key commanding the pausing and resumption of the supply        of gas.    -   the “Pause treatment” key and the “Resume treatment” key are        different keys.    -   according to another embodiment, the “Pause treatment” key and        the “End treatment” key are the one same key commanding a        definitive or temporary stopping (i.e. pausing) of the supply of        gas.    -   according to yet another embodiment, the “Start treatment” key        and the “Resume treatment” key are the one same key commanding a        start (i.e. initial or resumption after a pause) of the supply        of gas.    -   the control means are also configured to determine, from the        total number (N) of patients treated, which has been counted up,        and from the total treatment durations determined for the        treated patients:        -   the number of short treatments (TC) for which the total            treatment duration is below a preset threshold duration. In            other words, the number TC corresponds to the number of            patients who have undergone a treatment that has quickly            been interrupted, typically after less than 3 hours, because            this treatment was not effective, was having negative            side-effects or for some other reason, and/or        -   the number of long treatments (TL) for which the total            treatment duration is above said preset threshold duration.            In other words, the number TL corresponds to the number of            patients who have undergone a treatment of long duration            because it has been effective in these patients, for example            over a duration that may be as long as several days.    -   according to one particular embodiment, the control means are        also configured not to increment the total number (N) of        patients treated by +1 (i.e. not to count them) when the total        treatment duration determined is below a preset minimum duration        which is below the preset threshold duration, for example a        preset minimum duration less than or equal to 1 hour, preferably        less than or equal to 30 minutes. This is because use of the        device for a short minimum duration generally corresponds to an        exceptional situation that does not correspond to the treatment        of a patient, for example to correcting a setup error,        performing a demonstration for training purposes or the like,        which exceptional situation, in order not to falsify the        calculation of the total number (N) of patients treated, must        not be counted.    -   the number of long treatments (TL) is equal to the total        number (N) of patients treated minus the number of short        treatments (TC), namely:    -   TL=N−TC. Or, expressed differently, N=TC+TL or TC=N−TL.    -   the control means cooperate with the graphic display to also        display the number of short treatments (TC) and/or the number of        long treatments (TL).    -   it further comprises memory storage means configured to store:        -   the total number (N) of patients treated,        -   the number of short treatments (TC),        -   the number of long treatments (TL),        -   the choices selectable by the user, and/or        -   the preset threshold duration,        -   and/or possibly the preset minimum duration.    -   the threshold duration is less than or equal to 5 hours,        typically of the order of 3 h to 4 h, for example 3 h, when the        therapeutic gas is NO.    -   the minimum duration is less than or equal to 1 h, for example        of the order of 30 minutes.    -   the threshold duration is adjustable and/or the minimum duration        is adjustable.    -   the memory storage means comprise one or more memories for        recording and storing data, for example one or more volatile or        non-volatile memories, for example of the flash memory or some        other type.    -   at least one memory (e.g. flash) is sited on a or the electronic        board.    -   it further comprises electrical-current supply means which        supply electrical current to such components of the device as        require current in order to operate, such as the display, the        microprocessor, the memory . . . The electrical-current supply        means may, in the conventional way, comprise one (or more)        rechargeable or non-rechargeable battery(ies), a power cord and        an electric plug that can be connected to the mains network        (110/220 V), a current transformer, etc.    -   it further comprises a rigid external casing or housing in which        all or some of the components of the device are arranged,        particularly the control means, the internal passage, the valve        means, etc.    -   the graphic display is arranged in a wall of the rigid external        casing.    -   the control means are configured to control (at least) the valve        means so as to adjust the flow rate of therapeutic gas        circulating in the internal passage.    -   the valve means comprise at least one proportional        (electro)valve or several electrovalves, preferably several        electrovalves arranged in parallel.    -   it further comprises a flowmeter device arranged on the gas        passage so as to determine (i.e. measure) the flow rate of        therapeutic gas circulating in the internal passage.    -   the flowmeter device is of the hot-wire or differential-pressure        type.    -   the flowmeter device cooperates with the control means.    -   it comprises re-zeroing (RESET) means allowing the counter or        counters to be reset, for example a RESET key or the like.

The invention also relates to an installation for administering gas to apatient, comprising:

-   -   at least one source of therapeutic gas,    -   a therapeutic-gas supply device according to the invention,        supplied with therapeutic gas by said at least one source of        therapeutic gas, and    -   a gas supply line supplied with therapeutic gas by the        therapeutic-gas supply device.

According to the embodiment considered, the gas administeringinstallation of the invention may comprise one or more of the followingfeatures:

-   -   it further comprises a medical ventilator, that is to say a        ventilation assistance apparatus, in fluidic communication with        the gas supply line.    -   the medical ventilator is fluidically connected to the supply        line to supply said supply line with air or with an N₂/O₂        mixture.    -   the source(s) of therapeutic gas contain/s NO, particularly an        NO/N₂ mixture.    -   the source of therapeutic gas contains an NO/N₂ mixture        containing less than 2000 ppm by volume of NO, the rest being        nitrogen, preferably less than 1000 ppm by volume of NO, the        rest being nitrogen.    -   as a preference, the source of therapeutic gas contains an NO/N₂        mixture containing from 250 to 900 ppm by volume of NO, the rest        being nitrogen, for example of the order of 800 ppm by volume of        NO, the rest being nitrogen.    -   alternatively, at least one source of therapeutic gas contains        an O₂/N₂O mixture, preferably an equimolar (50/50 mol %) mixture        of oxygen and of nitrous oxide, i.e. contains MEOPA.    -   alternatively, the source of therapeutic gas contains oxygen,        and in particular comprises an oxygen container or an oxygen        line.    -   alternatively, the source of therapeutic gas contains argon or        an argon/oxygen mixture.    -   it further comprises a gas humidifier arranged on the gas supply        line, preferably downstream of the point at which the        therapeutic-gas supply device is fluidically connected to said        gas supply line so as to supply it with therapeutic gas.    -   it further comprises a line for recovering the gases exhaled by        the patient.    -   the gas supply line and the exhaled-gas recovery line are        connected to a connection piece, preferably a Y-piece, and        define a patient circuit.    -   the gas supply line forms an inspiratory branch of the patient        circuit.    -   the exhaled-gas recovery line forms an expiratory branch of the        patient circuit.    -   the gas supply line is fluidically connected to an outlet port        of the medical ventilator so as to collect and convey the gas        delivered by the medical ventilator.    -   the exhaled-gas recovery line is fluidically connected to an        inlet port of the medical ventilator so as to supply the medical        ventilator with all or some of the gases exhaled by the patient        and thus determine whether there is one or more potential gas        leaks.    -   the exhaled-gas recovery line potentially (i.e. this is not        compulsory) comprises a CO₂ removal device allowing the        elimination of the CO₂ present in the gases exhaled by the        patient.    -   the exhaled-gas recovery line potentially (i.e. this is not        compulsory) comprises a filter.    -   at least one source of therapeutic gas comprises one or more gas        container(s), particularly one or more pressurized-gas        cylinder(s).    -   the gas container(s) is/are equipped with a gas distribution        valve.    -   the gas distribution valve is a valve with or without inbuilt        regulator.    -   the gas distribution valve is made of copper alloy, such as        brass.    -   the gas container(s) is/are equipped with a protective bonnet        arranged around the gas distribution valve.    -   the bonnet is made of a polymer (i.e. plastic) material, of        metal, or of combinations of these.    -   the fluid container(s) is/are a pressurized-gas cylinder        containing, when full, a gas mixture, particularly NO/N₂, at a        pressure of at least 150 to 200 bar abs, or even at least 250 to        300 bar abs.    -   the fluid container has a cylindrical, particularly ogival,        overall shape.

According to another aspect, the invention also relates to a therapeutictreatment method involving administering to a patient a therapeutic gas,particularly NO, such as an NO/nitrogen mixture, wherein a gasadministering installation and/or a therapeutic-gas supply deviceaccording to the invention is/are used to supply to said patient saidtherapeutic gas, particularly NO, such as an NO/nitrogen mixture, to apatient suffering from pulmonary hypertension, whether this be an adult,an adolescent, a child or a newborn, for example a newborn sufferingfrom persistent pulmonary hypertension of the newborn (PPHN).

Depending on the embodiment considered, the NO/nitrogen mixture may bediluted with air or with a nitrogen/oxygen mixture before being suppliedto the patient. As a preference, the air or the nitrogen/oxygen mixtureis supplied by a medical ventilator.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be better understood by virtue of the followingdetailed description, which is given by way of non-limitingillustration, and with reference to the appended figures, in which:

FIG. 1 schematically indicates one embodiment of a therapeutic-gassupply device according to the invention,

FIG. 2 schematically indicates one embodiment of a gas administeringinstallation according to the invention, and

FIG. 3 schematically indicates one embodiment of a screen of the gassupply device according to the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 schematically indicates one embodiment of a therapeutic-gassupply device 1 according to the invention, comprising a rigid housing13, for example made of polymer, in which there is arranged an internalgas passage 2, such as a gas or similar duct, for conveying a flow oftherapeutic gas.

In this embodiment, we consider, by way of example of a therapeutic gas,a flow of gas based on NO, namely a mixture of nitric oxide and ofnitrogen, or NO/N₂.

The flow of NO-based gas enters and circulates in the internal gaspassage 2 between a (or more than one) gas inlet 3 and a gas outlet 4.The gas inlet 3 and outlet 4 may for example be borne by connectors ormechanical-connection and fluidic-connection end fittings borne by thehousing 13 of the device 1, to which gas lines used for conveying thegas, for example flexible tubes or the like, can be attached, asexplained hereinafter.

Valve means 5, i.e. a (or more than one) valve device(s), for example aplurality of electrovalves arranged in parallel, are arranged on theinternal gas passage 2 and allow control of the flow of therapeutic gasthat circulates in the internal passage 2 in the direction extendingfrom the gas inlet 3 to the gas outlet 4. Of course, use may also bemade of other valve means, for example a (or more than one) proportional(electro)valve(s).

The valve means 5 are operated by control means 6, i.e. a (or more thanone) control device(s), arranged in the housing 13, typically anelectronic board comprising a (or more than one) microprocessor(s),typically a (or more than one) microcontroller(s), running one or morealgorithm(s). The control means 6 notably make it possible to adjust orcontrol the flow rate of gas passing through the valve means 5.

In this way, the control means 6 can control the valve means 5, such aselectrovalves arranged in parallel, and namely can open or close all orsome of these valves in order to obtain a gas flow rate (Q)determined/calculated by the microcontroller on the basis of a valuethat is regulated/set for example by the user, and as a function of theflow rate (Q′) of gas, i.e. air, delivered by the ventilator 23, asexplained hereinafter.

A (or more than one) flowmeter (not depicted) is also provided, thisbeing arranged on the internal gas passage 2, upstream and/or downstreamof the valve means 5 so as to determine the flow rate (Q) of NO-basedgas. The flowmeter may be of the differential-pressure, hot-wire or someother type. It cooperates with the control means 6 in order to supplythem with measurements.

Moreover, the housing 13 comprises a graphic display 7, preferably atouchscreen, used to display various items of information or data,particularly various choices 9 a-9 d that a user can select. Thesechoices may be displayed in windows or the like displayed on thetouch/digital screen of the graphic display 7.

The graphic display 7 is also configured to show one or more curves,graphs, alarms, icons, etc. or any other item of information or data ofuse to the user, such as the care-giving staff.

Also provided are selection means 8, i.e. a (or more than one) selectiondevice, allowing the user to make a selection among the selectablechoices 9 a-9 d which are displayed on the graphic display 7, namely tochoose between several options proposed and displayed on the screen, orto confirm/validate or reject a choice (i.e. an option), or else to makeadjustments or settings, for example to select the desired value for theflow rate.

The selection means 8 typically comprise selection keys or buttons thatthe user can actuate. Advantageously, the selection means 8 are virtualkeys operated by touch, namely touch-sensitive keys, displayed on thegraphic display 7 which is itself a touchscreen.

According to the present invention, the control means 6 are alsoconfigured to count a total number (N) of patients treated byadministration of the therapeutic gas from the selection, by a user, viathe selection means 8, particularly a touch-sensitive key displayed onthe graphic display 7, of a first given choice 9 a corresponding to thestart of a treatment by administering the therapeutic gas to a patientconcerned. For example, the start of a treatment may be initiated by theuser pressing with a digit on a “Start treatment” key that commands thestart of the supply of therapeutic gas.

The total number (N) of patients treated is counted by incrementing acounter, for example a counter of the microprocessor or the like, inincrements of +1.

Stated differently, as soon as a treatment by administering therapeuticgas, such as NO, to a patient is to begin, the user presses on the“Start treatment” touch-sensitive key displayed on the graphic display7, which corresponds to the initiation, i.e. the starting, of thistreatment, and this increments by +1 the counter which keeps count ofthe total number (N) of patients treated.

The total number (N) of patients treated may be displayed on the graphicdisplay 7 either permanently, or on demand from the user, for exampleafter pressing a dedicated key.

As illustrated in FIG. 1, the graphic display 7 may display severalselectable choices 9 a-9 d each corresponding to a specific givenaction.

For example, the display 7 may display, in the form of keys or the like:

-   -   a first given choice 9 a corresponding to a start of the        treatment by administering the therapeutic gas to the patient,        namely a “Start treatment” key;    -   a second given choice 9 b corresponding to the end of the        treatment of the patient concerned, namely an “End treatment”        key;    -   a third given choice 9 c corresponding to a suspension of the        treatment with temporary interruption of the administration of        therapeutic gas to the patient concerned, namely a pausing of        the treatment by selecting a “Pause treatment” key; and    -   a fourth given choice 9 d corresponding to the resumption of the        treatment of the given patient by selecting a “Resume treatment”        key.

The user's selection of one of these choices 9 a-9 d, for example bypressing with a digit on the virtual key, for example a window or thelike, of the touchscreen of the display 7, will be transmitted to themicroprocessor of the control means 6 and the latter will control theoperation of the apparatus according to the selection made.

For example, the control means 6 may command the valve means 5 to:

-   -   allow gas to circulate in the internal passage 2, through the        flow-control electrovalve(s) according to the set flow rate (Q),        in the direction of the patient if the key pressed corresponds        to the first choice 9 a, namely corresponds to starting        treatment by administering the therapeutic gas to the patient,        namely corresponds to the “Start treatment” key;    -   interrupt the circulation of gas in the internal passage 2 in        the direction of the patient if the key pressed corresponds to        the second or third choice 9 b or 9 c, and therefore corresponds        to a definitive or temporary stopping of the treatment of the        patient, namely corresponds to an “End treatment” or “Pause        treatment” key; and    -   allow gas to circulate once again in the internal passage 2, in        the direction of the patient, if the key pressed corresponds to        the fourth choice 9 d, after the pressing of the key for the        third choice 9 c synonymous with temporarily stopping the        treatment , i.e. temporarily pausing the treatment, by selecting        the “Resume treatment” key.

In the embodiment of FIG. 1, the 4 keys 9 a-9 d are individual keys eachperforming a specific action. However, some of the actions/choicescould, according to other embodiments, be selected using the one samekey, which means to say that the one same key could be used to select anumber of different choices.

For example, the third and fourth choices 9 c and 9 d are displayed inthe form of two, “Pause treatment” and “Resume treatment”, virtual keysor the like. However, according to another embodiment, these third andfourth choices 9 c, 9 d could be selected by the one same “Pause/Resumetreatment” virtual key.

Likewise, according to yet another embodiment, the first, third andfourth choices 9 a, 9 c, 9 d could be selected by the one same“Start/Pause/Resume treatment” virtual key.

According to yet another embodiment, the one same key could command thestart and resumption of the treatment after a pause, and another keycould command the temporary pausing and the definitive ending of thetreatment.

Of course, other combinations or embodiments are also possible.

In all cases, a pressing, i.e. selection by the user, on the key or thelike corresponding to the first choice 9 a, namely to a start oftreatment in a patient concerned (i.e. new patient), causes the counterof the number of patients treated to be incremented by +1 and no furtherincrementation by +1 can take place until after the key corresponding tothe second choice 9 b, namely the key signalling the definitive end oftreatment of the patient concerned, has been pressed. It must beemphasized that a selection of choices 9 c, 9 d corresponding to pausingand/or resuming a treatment does not lead to any incrementing of thecounter.

According to a variant embodiment, the start of a treatment byadministering therapeutic gas to a patient cannot begin until after theuser has validated, i.e. confirmed, the first choice selected bypressing the “Start treatment” key; as a preference, validation isperformed by the user selecting a dedicated Validate key, particularly avirtual Validate key displayed on the graphic display 7 as detailedhereinbelow.

In other words, the control means 6 are configured to operate the valvemeans 5 and begin the supply of therapeutic gas only after the user hasselected the first given choice of “Start treatment” and then confirmedthis choice by pressing the Validate key.

Furthermore, according to a more sophisticated embodiment of theinvention, the control means 6 are also configured to determine a totaltreatment duration for each patient treated which corresponds to theperiod of time elapsed between the user selecting the first given choice9 a corresponding to the start of a treatment by administering thetherapeutic gas to a patient concerned, and the second given choice 9 bcorresponding to the definitive end of the treatment by administeringtherapeutic gas to the patient concerned.

As a result, the control means 6 are configured to temporarilyinterrupt, i.e. stop, determining the total treatment duration for apatient concerned after the user selects the third given choice 9 ccorresponding to pausing the treatment with temporary interruption ofthe administration of therapeutic gas to the patient concerned, and thenresume determining the total treatment duration after:

-   -   either the user reselects the first given choice 9 a        corresponding to the start of a treatment by administering the        therapeutic gas,    -   or the selection of a fourth given choice 9 d corresponding to        resumption of a treatment by administering the therapeutic gas        to the patient concerned.

According to yet another embodiment of the invention, the control means6 may also be configured to determine:

-   -   the number of short treatments (TC) for which the total        treatment duration is below a preset threshold duration, i.e.        the number of patients that have undergone such a short-duration        treatment, for example of under 3 h, and/or    -   the number of long treatments (TL) for which the total treatment        duration is above the preset threshold duration, where TL=N−TC,        where N is the total number of patients treated, i.e. the number        of patients that have undergone such a long-duration treatment,        for example of over 3 h, and which may last for as much as 1 to        several days.

The control means 6 cooperate with the graphic display 7 to display 11,12 the value or values thus determined, namely the number of shorttreatments (TC) and/or the number of long treatments (TL).

Specifically, being able to determine and display the number of shorttreatments (TC) and the number of long treatments (TL) out of the totalnumber of patients treated, namely the total number of treatments givenusing the device concerned, makes it possible to make a distinctionbetween those patients that have been responsive to the treatment, whichis to say those for whom the gas has worked, and those for whom the gashas had no therapeutic effect despite having been administered for aminimum duration, which is to say a duration that may reach the presetthreshold duration. Such information is very useful to the care-givingstaff, notably in order to decide whether perhaps to change thetreatment.

For example, for an iNO treatment, said threshold duration may be set at3 hours or at some other “short” duration. Treatments that are stoppedbefore the 3-hour mark will be counted as short treatments (TC) thathave had no appreciable or proven therapeutic effect in the patients,and those which have lasted at least 3 hours will be counted as longtreatments (TL) that have had a beneficial effect on the patients.

In general, the counting of the patients treated with the gasadministering device 1 of the invention is handled by an algorithm runby a microprocessor of the control means 6 of the device 1. Thisalgorithm counts up the total number (N) of patients treated byincrementing a counter. This number N is displayed on the screen 7 inorder to provide this information to the user. It is preferably recordedin a non-volatile memory.

Advantageously, the device 1 is also able to take into account thestarting of a complete new treatment (i.e. new treatment for a newpatient), a temporary pausing of treatment, the resumption of atreatment of an unstable patient in the withdrawal phase (i.e.resumption of a treatment that had been paused) and a “short” treatmentwhen the duration of administration of a new treatment is less than afew hours (i.e. preset threshold duration), signifying that the patientis not responding to the treatment given.

The unique triggering event that causes the counter of the total number(N) of patients treated to be incremented by +1 is the action ofselecting a first choice 9 a displayed on the touchscreen of the display7 corresponding to “Start new treatment” by pressing a virtual key orthe like displayed on the screen, corresponding to this first choice 9a.

When it is necessary to temporarily pause the treatment of a givenpatient, the device 1 may offer a choice or a selection corresponding totemporarily pausing the treatment, in the form of a dedicated key 9 c ofthe “Pause treatment” type, as explained hereinabove.

When resuming a treatment, for example after a lengthy pause, the device1 may request confirmation, i.e. validation of the choice, beforeincrementing the counter, for example by asking the user to select a“Yes” or “No” answer to a question of the type: “Is this a new patient?”and by offering two possible choices of answer “Yes” and “No” in theform of two virtual keys displayed on the screen. The answer “No” istreated by the device 1 as being a restart after a pause in treatmentand not as a new patient; therefore the counter is not incremented.

The total treatment time is determined by the control means 6 as beingthe duration extending between the user pressing the key 9 a signifying“Start new treatment” and subsequent pressing on another keycorresponding to a choice 9 b of the “Stop treatment” type, or even onanother key corresponding to a third choice 9 c of the “Pause treatment”type with the treatment not then being subsequently resumed with thesame patient, as explained hereinabove.

Advantageously, the display 7 displays not only the total number (N) ofpatients treated (at 10) but also the number of short treatments TC (at11) and the number of long treatments TL, which is to say completetreatments (at 12). The total number (N) of patients treated is equal tothe sum of the total number of long treatments and the number of shorttreatments (i.e. N=TL+TC).

The display 10, 11, 12 of all or some of the values N, TL and TC may beavailable permanently on the graphic display 7 or else may appear on thescreen only after being called up by the user, for example by pressing adedicated key or the like.

FIG. 2 schematically indicates one embodiment of a gas administeringinstallation 20 according to the invention, in this instance comprisingtwo cylinders 21 of therapeutic gas, namely in this instance NO/N₂mixtures, for example containing 800 ppm by volume of NO (the rest beingN₂), which supply an NO/N₂ mixture to a therapeutic-gas supply device 1according to the invention, as illustrated in FIG. 1 and describedhereinabove.

The gas cylinders 21 are fluidically connected to the gas supply device1 via gas conveying lines 30, such as flexible tubes or the like, whichmay be fitted with gas-pressure regulating and/or monitoring devices 31,such as pressure regulators, pressure gauges, etc. The gas conveyinglines 30 are connected to one or more gas inlets 3 of the gas supplydevice 1 which supply the internal passage 2 of said gas supply device.

It will be noted that the gas supply device 1 also comprises an oxygeninlet 32 fluidically connected, via an oxygen conveying line 34, such asa flexible tube or the like, to a source of oxygen, for example thehospital network, namely an oxygen supply line running through thehospital building.

Furthermore, a medical ventilator 23, namely a respiratory assistanceapparatus, is also provided to supply air or an oxygen/nitrogen (N₂/O₂)mixture, namely a flow of respiratory gas containing at least 21%oxygen.

The medical ventilator 23 and the gas supply device 1 are in fluidiccommunication with a gas supply line 22 used to carry the flow of gas tothe patient.

The gas supply device 1 delivers an NO/N₂ mixture, for example 800 ppmvof NO, into the gas supply line 22, via an injection pipe 37, so as toinject (at 37 a) a flow of NO/N₂ into the flow of air or ofoxygen/nitrogen mixture delivered by the medical ventilator 23.

The gas supply line 22 further comprises a gas humidifier 24 arrangeddownstream of the point (at 36) at which the therapeutic-gas supplydevice 1 is fluidically connected to the supply line 22. This gashumidifier 24 allows the flow of gas, e.g. NO/N₂/air mixture, to behumidified before it is inhaled by the patient, via a patientrespiratory interface, such as a tracheal tube or the like. In FIG. 2the patient/interface assembly is indicated schematically as an“artificial lung” 25.

A line 27 for recovering the gases exhaled by the patient is alsoprovided. The gas supply line 22 and the exhaled-gas recovery line 27are connected to a connection piece 28, preferably a Y-piece, and thusdefine a patient circuit 29. The gas supply line 22 forms theinspiratory branch of the patient circuit 29, while the exhaled-gasrecovery line 27 forms the expiratory branch of the patient circuit 29.

The gas supply line 22 is fluidically connected to an outlet port 23 aof the medical ventilator so as to collect and convey the gas, typicallyair (or an N₂/O₂ mixture containing around 21% O₂), delivered by themedical ventilator 23, while the exhaled-gas recovery line 27 isfluidically connected to an inlet port 23 b of the medical ventilator 23so as to supply the medical ventilator 23 with all or some of the flowof gases exhaled by the patient.

The exhaled-gas recovery line 27 may comprise one or more other optionalcomponents 26, such as, for example, a device for eliminating the CO₂,i.e. a CO₂ trap, such as a hot pot or the like, allowing the removal ofthe CO₂ present in the gases exhaled by the patient, or a filter or thelike. Specifically, a device for eliminating the CO₂ may provebeneficial when the gas contains N₂O that needs to be recovered after ithas been exhaled by the patient. The exhaled-gas recovery line 27 isused, in the case of NO, by the ventilator 23 to check whether there isa gas leak in the circuit 22, 27 for example.

A flow rate sensor 36, for example of the hot-wire ordifferential-pressure type, is also provided, connected to the gassupply device 1 via a flow rate measurement line 35 used for measuringthe flow rate of gas (Q′), such as air (i.e. N₂/O₂), coming from theventilator 23, within the supply line 22 upstream of the point (at 37 a)of NO/N₂/air connection and mixing. As explained hereinabove, thisnotably allows the passage of the NO through the electrovalves 5 of thedevice 1 to be regulated.

Furthermore, a gas withdrawing line 38 fluidically connecting the gassupply device 1 to the supply line 22 in the vicinity of the Y-piece 28may be provided so that samples of gas can be taken and their compliancewith the desired mixture that is to be administered to the patientverified. The withdrawing line 38 is connected to the duct 22 downstreamof (at 38 a) the point 37 a of connection of the injection duct 37, whenconsidering the direction in which the flow of gas circulates from theventilator 23 towards the patient.

FIG. 3 schematically indicates one embodiment of the screen of thegraphic display 7 for a gas supply device 1 according to the invention,and which is configured to display various items of information, such asthe NO, O₂ and NO₂ concentrations in the gas but also, according to theinvention, a “Start treatment” touch-sensitive key (i.e. window)allowing the user, i.e. a caregiver, to select a first choice 9 acorresponding to the starting of a treatment by administering NO to apatient, and also incidentally the number “N” (at 10) of patients thathave been treated with this device 1.

In this embodiment, the other choice or choices 9 b-9 d are notdisplayed until after the user has selected the first choice 9 a, i.e.until after the window that forms a touch-sensitive key on thetouchscreen has been pressed.

Because the problems with recording the number of patients treated is awide-ranging problem for public and private hospital settings alike, thedevice of the invention can be used for treatments other than that ofinhaled nitric oxide, i.e. iNO, for example for treatments using anequimolar mixture of oxygen and nitrous oxide, such as MEOPA, or usingother gases, for example argon.

1. Device (1) for supplying therapeutic gas, comprising: an internalpassage (2) for conveying a flow of therapeutic gas between a gas inlet(3) and a gas outlet (4), valve means (5) for controlling the flow oftherapeutic gas in the internal passage (2), control means (6)configured to control at least the valve means (5), a graphic display(7) configured to display choices (9 a-9 d) that can be selected by auser, and selection means (8) configured to make a selection from amongthe selectable choices (9 a-9 d) displayed on the graphic display (7),wherein the control means (6) are configured to count a total number (N)of patients treated by administration of the therapeutic gas from theselection, by a user, via the selection means (8), of a first givenchoice (9 a) corresponding to the start of a treatment by administeringthe therapeutic gas to a patient concerned.
 2. The device according toclaim 1, wherein the control means (6) cooperate with the graphicdisplay (7) to display (10) the counted total number (N) of patientstreated.
 3. The device according to claim 1, wherein the control means(6) comprise at least one microprocessor.
 4. The device according toclaim 1, wherein the selection means (8) comprise selection keys and/orthe graphic display (7) comprises a touchscreen.
 5. The device accordingto claim 4, wherein the graphic display (7) comprises a touchscreen andthe selection keys are virtual keys displayed on the touchscreen.
 6. Thedevice according to claim 1, wherein the control means (6) areconfigured to count a total number (N) of patients treated byincrementing a patients counter.
 7. The device according to claim 1,wherein the control means (6) are configured to increment the totalnumber (N) of patients treated by +1 in response to a selection, by theuser, of the first given choice (9 a) corresponding to the start of atreatment by administering therapeutic gas to a patient concerned. 8.The device according to claim 1, wherein the control means (6) are alsoconfigured to determine a total duration of treatment for each patienttreated which corresponds to the period of time elapsed between the userselecting: the first given choice (9 a) corresponding to the start of atreatment by administering the therapeutic gas to a patient concerned,and a second given choice (9 b) corresponding to the end of thetreatment by administering the therapeutic gas to said patientconcerned.
 9. The device according to claim 8, wherein the control means(6) are also configured to: a) temporarily interrupt the determining ofthe total duration of treatment for a patient concerned after: eitherthe user selects the second choice (9 b) corresponding to the end of thetreatment, or the user selects a third given choice (9 c) correspondingto a suspension of treatment with temporary interruption of theadministration of therapeutic gas to said patient concerned, and b)resume determining the total duration of treatment for said patientconcerned after: either the user reselects the first given choice (9 a)corresponding to the start of a treatment by administering thetherapeutic gas, or the user selects a fourth given choice (9 d)corresponding to resumption of a treatment by administering thetherapeutic gas to said given patient.
 10. The device according to claim6, wherein the control means (6) are also configured not to incrementthe patients counter after the user reselects the first choice (9 a)corresponding to the start of a treatment or selects the fourth choice(9 d) corresponding to the resumption of treatment for a given patient.11. The device according to claim 8, wherein the control means (6) arealso configured to determine, from the total number (N) of patientstreated, which has been counted up, and from the total treatmentdurations determined for the treated patients: i) the number of shorttreatments (TC) for which the total treatment duration is below a presetthreshold duration, and/or ii) the number of long treatments (TL) forwhich the total treatment duration is above said preset thresholdduration.
 12. The device according to claim 11, wherein the controlmeans (6) cooperate with the graphic display (7) to also display (11;12) the number of short treatments (TC) and/or the number of longtreatments (TL).
 13. Installation (20) for administering gas to apatient, comprising: at least one source of therapeutic gas (21), atherapeutic-gas supply device (1) according to claim 1, supplied withtherapeutic gas by said at least one source of therapeutic gas (21), anda gas supply line (22) supplied with therapeutic gas by thetherapeutic-gas supply device (1).
 14. The installation according toclaim 13, further comprising a medical ventilator (23) in fluidiccommunication with the gas supply line (22).
 15. The installationaccording to claim 13, wherein at least one source of therapeutic gas(21) contains an NO/N₂ or O₂/N₂O mixture.
 16. The device according toclaim 1, wherein the control means (6) are configured to count a totalnumber (N) of patients treated by incrementing a patients counter, andwherein the patients counter is a counter internal to a microprocessor.17. The installation according to claim 13, wherein at least one sourceof therapeutic gas (21) contains an NO/N₂ or O₂/N₂O mixture stored inone or more gas containers.
 18. The device according to claim 1, whereinthe control means (6) comprise at least one microcontroller.
 19. Thedevice according to claim 2, wherein the control means (6) comprise atleast one microprocessor.
 20. The device according to claim 6, whereinthe control means (6) are configured to increment the total number (N)of patients treated by +1 in response to a selection, by the user, ofthe first given choice (9 a) corresponding to the start of a treatmentby administering therapeutic gas to a patient concerned.